2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

SOLVED E-Fan VS stock clutch Fan with FMIC

Thread Tools
 
Search this Thread
 
Old 08-15-15, 08:34 PM
  #1  
Rotary Enthusiast

Thread Starter
iTrader: (8)
 
immanuel__7's Avatar
 
Join Date: Mar 2004
Location: Ontario
Posts: 1,036
Likes: 0
Received 0 Likes on 0 Posts
SOLVED E-Fan VS stock clutch Fan with FMIC

Ok so i build a new engine for my Fc. I use a 60-1 hybrid turbo setup. keep the A/c condenser, stock rad, and... mount a big Ebay FMIC behind the bumper and used a dual speed taurus E-Fan . ran the car. started tuning and found a that the efan was killing my voltage and the fuel pump was not able to keep up to fuel demands, so i bumped up the temps from 190f for the efan, so i bumped set point to 210F then 215F im on the highway doing 110km/h at night with ambient temps 73F, intake temps are 140F and efan is turning on and off while im cursing.... figured i need a new bigger rad. did some research found ppl saying to duct and plug any holes to allow all air to flow to rad. did this same prob. installed the stock clutch fan and shroud. took the car for a drive. O my the car is maxes out at 185F the odd 186F and drops as low as 175F. intake temp are as low as 100F now as well. See attched data logs
what a difference, plus no i find my engine bay temps are much lower(with i would have used my works remote temp probs to test temp difference) o well

(please note the high temp one yes im on and off the throttle as i could only access when efan shut off )
I just noticed you can actually see the T-stat opening on the log now

Im sure this horse has been flogged many times lol.
but figured id post some concrete numbers with true logs,

Disclaimer notes: all temp sensors used in this experiment were calibrated using ice water, boiling water and 100F water to give sensors there full range
Attached Thumbnails SOLVED E-Fan VS stock clutch Fan with FMIC-stock-fan.png   SOLVED E-Fan VS stock clutch Fan with FMIC-efan.png  
Old 08-15-15, 10:42 PM
  #2  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
Well, kudos for posting some data but your timeline and methodology are kinda confusing.

Did you get a new/bigger rad or not and if so, when?
At your low ambient temp and speed (and, I assume, RPM), the car should have been running cool as a cucumber and yet you reached at least 217°. I'd figure your cooling package (including ducting) needs reevaluation, an opinion based on the significant drop in IAT.

I can see the water temp varying but the intercooler is first in line for fresh air, on the highway it is theoretically at least getting all it can drink. Your intake temp dropped a lot when the fan was constantly pulling and that means your setup is restricting airflow from behind the intercooler (which the fan helps alleviate). You achieve the same result- probably better- with an extractor setup on the hood.

Why didn't you address your subpar alternator before raising the fan trigger start temp?
Seems like that intentionally crippled the fan as it was still undervolted when it did start but with a greater heat load than before.
Old 08-15-15, 11:32 PM
  #3  
Rotary Enthusiast

Thread Starter
iTrader: (8)
 
immanuel__7's Avatar
 
Join Date: Mar 2004
Location: Ontario
Posts: 1,036
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by clokker
Well, kudos for posting some data but your timeline and methodology are kinda confusing.

Did you get a new/bigger rad or not and if so, when?
I did not upgrade the rad i kept the stock S4

Originally Posted by clokker
At your low ambient temp and speed (and, I assume, RPM), the car should have been running cool as a cucumber and yet you reached at least 217°. I'd figure your cooling package (including ducting) needs reevaluation, an opinion based on the significant drop in IAT.

I can see the water temp varying but the intercooler is first in line for fresh air, on the highway it is theoretically at least getting all it can drink. Your intake temp dropped a lot when the fan was constantly pulling and that means your setup is restricting airflow from behind the intercooler (which the fan helps alleviate). You achieve the same result- probably better- with an extractor setup on the hood.
I was wounderng about hood work as well. if the A:the stock TII hood was causing some sort of turbulance and or back pressure keep the heat in the engine bay sort of speak. an extractor would help Tones im sure.

Originally Posted by clokker
Why didn't you address your subpar alternator before raising the fan trigger start temp?
Seems like that intentionally crippled the fan as it was still undervolted when it did start but with a greater heat load than before.
I had 12V running the E-fan if i did not try to accelerate the car(as fuel pump is hungry for power!) i could see the voltage on the megasquirt, at times id see 11V but for the most part id see 12v(i understand its not the 14V it could see and 2V DC is big in a since, on an other note seeing as i could drive 110khm and not keep the car cool on its own that made me dig into rx7club.com and search efan set ups and found pros and most pros for stock fan, so i installed figured it was a simple enough tasks. the "subpar alternator" is or was a problem using the Efan, i did try the S5 alt with zero gauge wire all around to try and fix the voltage problems during E-fan use, but i figured if i can cure this problem with out spending any more cash then i need to Y not!

Originally Posted by clokker
your setup is restricting airflow from behind the intercooler
I do agree my setup is restrictive, the stock bumper was oddly enough not design for a big FMIC, i in theory should upgrade the front bumper to allow more forced air flow. but once more curing the problem by going back to stock fan for no extra cash spent. i have also left a 3 to 4" gap under the FMIC to try and flow more air to the condenser/oil cooler/rad when i installed the FMIC, not sure if this hindered my air flow but seeing as others have had the same problems i had im reluctant to think it is affecting the flow. could be wrong as i am most of the time hahah.

I do like your points tho. and are all valid!

Last edited by immanuel__7; 08-15-15 at 11:41 PM.
Old 08-15-15, 11:49 PM
  #4  
Rotary Enthusiast

Thread Starter
iTrader: (8)
 
immanuel__7's Avatar
 
Join Date: Mar 2004
Location: Ontario
Posts: 1,036
Likes: 0
Received 0 Likes on 0 Posts
this graph was an other day with lower fan set point, i believe it was set for 210F on and off at 203F its a tad more linear then the first pic with less heat load to remove but car still keep needing efan to keep setpoint.
Attached Thumbnails SOLVED E-Fan VS stock clutch Fan with FMIC-other-day.png  
Old 08-16-15, 10:04 AM
  #5  
Engine, Not Motor

iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes on 91 Posts
I'm not sure I follow what's going on.

The car didn't cool down with the Taurus fan?

Then did with the stock fan?

As for the voltage issues, yes, sticking a massively inefficient piece of junk fan like the Taurus fan on a stock alternator is going to completely overload the system.

Bumper a limitation? I drive around all day in 30 degree weather with a stock S4 bumper, FMIC, Fluidyne rad and Pontiac 6000/Oldsmobile/Grand AM/GM 90s fan without temperature issues.
Old 08-16-15, 01:10 PM
  #6  
Rotary Enthusiast

Thread Starter
iTrader: (8)
 
immanuel__7's Avatar
 
Join Date: Mar 2004
Location: Ontario
Posts: 1,036
Likes: 0
Received 0 Likes on 0 Posts
Yes I could not keep the car cool with Taurus fan even at highway speeds.
installed the stock fan and Temps never go past 185f in town or highway even with 30th days like this past sat
Old 08-16-15, 10:09 PM
  #7  
Living on the North Coast

iTrader: (31)
 
DeaconBlue's Avatar
 
Join Date: Mar 2009
Location: Avon Lake
Posts: 600
Received 7 Likes on 7 Posts
When installing a E-fan you really must upgrade from the sub-par 70A S4 or 80A S5 alternator. Try the 100A FD unit. You may even want to upgrade the cable from the alternator to the fuse box from the stock 6ga cable to say 4ga cable. You can then upgrade the main fuse from 100A to say a 120-125A unit.

The stock radiator, a/c condenser, oil cooler and a FMIC all add up to too much restriction to air flow as well as too much heat that needs to be rejection at lower speeds. You may want to start with a 180 degree thermostat and then select the e-fan controller settings accordingly.
Old 08-16-15, 11:03 PM
  #8  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
Originally Posted by immanuel__7
Yes I could not keep the car cool with Taurus fan even at highway speeds.
installed the stock fan and Temps never go past 185f in town or highway even with 30th days like this past sat
Well, you'd clearly benefit from a reconfigured cooling arrangement as you shouldn't need any fan at low stress highway speeds.

But be that as it may, did you wonder how the efan would have done if you'd run it constantly like the clutch fan does?
After you'd fixed the alternator situation, of course.
Old 08-17-15, 08:25 AM
  #9  
destroy, rebuild, repeat

iTrader: (1)
 
gxl90rx7's Avatar
 
Join Date: May 2004
Location: Charleston, SC
Posts: 2,990
Likes: 0
Received 16 Likes on 14 Posts
really the root of your problem is the FMIC, they block too much flow to the radiator. V-mount configuration would be ideal. FMIC on an rotary, horrible combination

anyway the stock fan is probably more efficient than an e-fan, but its all tradeoffs. I would rather have inefficient efan and have easier to work engine bay. your comparison is not really fair because your alternator isnt up to the task of powering an e-fan

Last edited by gxl90rx7; 08-17-15 at 08:27 AM.
Old 08-17-15, 08:42 AM
  #10  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
Originally Posted by gxl90rx7
anyway the stock fan is probably more efficient than an e-fan, but its all tradeoffs.
By any metric I can think of, the thermoclutch is LESS efficient than an efan.
Old 08-18-15, 08:00 AM
  #11  
Sharp Claws

iTrader: (30)
 
RotaryEvolution's Avatar
 
Join Date: Oct 2003
Location: Central Florida
Posts: 5,107
Likes: 0
Received 41 Likes on 40 Posts
efficiency maybe, airflow not a chance.

i've been through this debate a thousand times and ill toss a stocker on before ANY e-fan any day. that doesn't even touch on the fact that there is 100 things to go wrong with the electrical portion of an e-fan versus the 2 things that can go wrong with the stock thermofan.
Old 08-18-15, 08:28 AM
  #12  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
Boy howdy, I'll tell ya, that efan requires a RELAY! and you practically need a doctorate to figger that sumbitch out.
And apparently, there are 99 other problems I haven't run into yet.
Old 08-18-15, 08:30 AM
  #13  
whats going on?

iTrader: (1)
 
SirCygnus's Avatar
 
Join Date: Mar 2004
Location: atlanta ga
Posts: 4,929
Received 8 Likes on 7 Posts
/me grabs the popcorn.
Old 08-18-15, 03:37 PM
  #14  
Sharp Claws

iTrader: (30)
 
RotaryEvolution's Avatar
 
Join Date: Oct 2003
Location: Central Florida
Posts: 5,107
Likes: 0
Received 41 Likes on 40 Posts
Originally Posted by clokker
Boy howdy, I'll tell ya, that efan requires a RELAY! and you practically need a doctorate to figger that sumbitch out.
And apparently, there are 99 other problems I haven't run into yet.
like a fan motor seizing, fuse holder melting, thermocontroller failing.. among other things.


yeah i've had just about every single thing fail that can fail in my car occur, and i'm not a complete tool when it comes to wiring electrical components. however there sure is a plethora of junk controllers and fans floating around out there.

kinda shitty when your $260 black magic fan locks and your water temps hit 260F before you notice it on a freshly built engine, stuck in the middle of traffic on a 108F day. i grabbed that bitch and spun it by hand until it kicked on enough to cool the car off enough to get on the freeway, where my temps were still creeping up. because no matter what you all say, you DO need a fan below 70mph if your intercooler is in front of the radiator, but you're welcome to test that theory on your own.

Last edited by RotaryEvolution; 08-18-15 at 03:46 PM.
Old 08-18-15, 05:00 PM
  #15  
Senior Member

iTrader: (6)
 
freq's Avatar
 
Join Date: Jan 2006
Location: Colorado
Posts: 679
Received 2 Likes on 2 Posts
Originally Posted by Lyger
like a fan motor seizing, fuse holder melting, thermocontroller failing.. among other things.


yeah i've had just about every single thing fail that can fail in my car occur, and i'm not a complete tool when it comes to wiring electrical components. however there sure is a plethora of junk controllers and fans floating around out there.

kinda shitty when your $260 black magic fan locks and your water temps hit 260F before you notice it on a freshly built engine, stuck in the middle of traffic on a 108F day. i grabbed that bitch and spun it by hand until it kicked on enough to cool the car off enough to get on the freeway, where my temps were still creeping up. because no matter what you all say, you DO need a fan below 70mph if your intercooler is in front of the radiator, but you're welcome to test that theory on your own.
Agreed. Bang for the buck (bang being defined as reliability and 'cool-ability'), you're not gonna do better than a stock fan. Seems there are a number of forum members that are, for some reason, attached to efans, but I would assume that most would rethink things after an engine meltdown because a fuse blew or a relay died.
Old 08-18-15, 05:31 PM
  #16  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
Originally Posted by Lyger
kinda shitty when your $260 black magic fan locks and your water temps hit 260F before you notice it on a freshly built engine, stuck in the middle of traffic on a 108F day. i grabbed that bitch and spun it by hand until it kicked on enough to cool the car off enough to get on the freeway, where my temps were still creeping up. because no matter what you all say, you DO need a fan below 70mph if your intercooler is in front of the radiator, but you're welcome to test that theory on your own.
My takeaway from this is not to use a Black Magic fan, keep an eye on the water temp gauge and don't intentionally block the rad with other components.

Originally Posted by freq
Agreed. Bang for the buck (bang being defined as reliability and 'cool-ability'), you're not gonna do better than a stock fan. Seems there are a number of forum members that are, for some reason, attached to efans, but I would assume that most would rethink things after an engine meltdown because a fuse blew or a relay died.
I kinda like the efan because it actually responds to water temp and unlike the stocker, it cools just as well at low rpm as high.

I guess I just like living on the edge.
Old 08-18-15, 06:42 PM
  #17  
Senior Member

iTrader: (6)
 
freq's Avatar
 
Join Date: Jan 2006
Location: Colorado
Posts: 679
Received 2 Likes on 2 Posts
Originally Posted by clokker
My takeaway from this is not to use a Black Magic fan, keep an eye on the water temp gauge and don't intentionally block the rad with other components.


I kinda like the efan because it actually responds to water temp and unlike the stocker, it cools just as well at low rpm as high.

I guess I just like living on the edge.

Well, I guess the bottom line is this...Both the efan and the stock fan have pro's and con's-figure out what works for your comfort level and your vehicle setup and roll with it.
Old 08-18-15, 09:11 PM
  #18  
Sharp Claws

iTrader: (30)
 
RotaryEvolution's Avatar
 
Join Date: Oct 2003
Location: Central Florida
Posts: 5,107
Likes: 0
Received 41 Likes on 40 Posts
Originally Posted by clokker
My takeaway from this is not to use a Black Magic fan, keep an eye on the water temp gauge and don't intentionally block the rad with other components.
yeah i know, i've also said the same thing in the past. but truth is no one watches their temp gauge 24/7 and it only takes 2 minutes to go from normal to about to explode hot.

the intercooler really had nothing to do with the fan failure though, simply exacerbates the issue of airflow issues that the FC has always been presented with.

in all honesty it's given me ideas to redesign my own V-mount that doesn't suck *** like the rest, using the space that no one utilizes.

Last edited by RotaryEvolution; 08-18-15 at 09:15 PM.
Old 08-19-15, 09:16 AM
  #19  
FC guy

iTrader: (8)
 
Rob XX 7's Avatar
 
Join Date: Oct 2002
Location: Long Island, New York
Posts: 8,714
Received 16 Likes on 16 Posts
im going to mount an intercooler on the roof
Old 08-19-15, 09:46 AM
  #20  
MECP Certified Installer

 
jjwalker's Avatar
 
Join Date: Feb 2009
Location: Mesquite, TX-DFW
Posts: 3,176
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by Rob XX 7
im going to mount an intercooler on the roof
I worked on a car about a month ago (porsche...maybe) and the intercooler was under the car and parallel to the ground.
Old 08-19-15, 02:48 PM
  #21  
Rotary Enthusiast

Thread Starter
iTrader: (8)
 
immanuel__7's Avatar
 
Join Date: Mar 2004
Location: Ontario
Posts: 1,036
Likes: 0
Received 0 Likes on 0 Posts
Well its been close to a week now and temps are keeping true to 185F. even on these humid 86F days we've been getting.
id like to see a dyo log of and e-fan vs stock fan and see the difference in hp if any. I might have to try that out when the car is tuned. (load on alt vs load from fan and clutch)


Originally Posted by clokker
Boy howdy, I'll tell ya, that efan requires a RELAY! and you practically need a doctorate to figger that sumbitch out.
And apparently, there are 99 other problems I haven't run into yet.
on that note:
i have seen 40amp relays cooked, bad contacts, coils dies, rusted/corroded water/condensation got in them. we used a 75$ thermostatic relay build for automotive use a while back when a friend and my self had FB's we placed the temp bulb in the rad fins worked ok for a few months till the fins got lose. so we installed them mounted to the rad hose but did not seance ok. instructions said we could insert them inside the coolant hose. so we did. my friend lost in sensing bulb inside the cooling system :0 and never found it haha. bearings on fan,
Cat stuck in fan blades... o wait thats the stock fan
Old 08-19-15, 04:24 PM
  #22  
Sharp Claws

iTrader: (30)
 
RotaryEvolution's Avatar
 
Join Date: Oct 2003
Location: Central Florida
Posts: 5,107
Likes: 0
Received 41 Likes on 40 Posts
Originally Posted by jjwalker
I worked on a car about a month ago (porsche...maybe) and the intercooler was under the car and parallel to the ground.
and i have done the same, here is an RX8 i built with a V mount and all stock radiator with A/C.

it is actually flush with the bottom of the front bumper, the angle makes it appear lower than it really is. i'll probably work out something similar with my FC. and yes it was ducted and enclosed, this was just an illustration of mounting.


Last edited by RotaryEvolution; 08-19-15 at 04:29 PM.
Old 08-19-15, 06:40 PM
  #23  
Senior Member
 
fc323's Avatar
 
Join Date: Jan 2010
Location: los angeles
Posts: 324
Likes: 0
Received 1 Like on 1 Post
You guys make it seem as though at any second, by your very breath, the e-fan will take out your engine and family. I mean, my fuel pump is also an electric motor operated by a relay, and im still alive. I understand you guy's reservation for electronic things over mechanical, but : Stop being old, and the stock e-fan on the fc is still working for me. It should be dead by you guy's standards, but it still kickin.
Old 08-20-15, 07:21 AM
  #24  
Sharp Claws

iTrader: (30)
 
RotaryEvolution's Avatar
 
Join Date: Oct 2003
Location: Central Florida
Posts: 5,107
Likes: 0
Received 41 Likes on 40 Posts
whatever, e-fans have caused severe overheating several times for me even when i try to watch water temps like a hawk.

personally i dislike them, they have their place which to me is on a car that no longer can accomodate the mechanical fan.
Old 08-20-15, 07:34 AM
  #25  
Original Gangster/Rotary!


iTrader: (213)
 
GoodfellaFD3S's Avatar
 
Join Date: Mar 2001
Location: FL-->NJ/NYC again!
Posts: 30,525
Received 538 Likes on 325 Posts
^This Lion/Tiger hybrid speaks the TRUTH


Quick Reply: SOLVED E-Fan VS stock clutch Fan with FMIC



All times are GMT -5. The time now is 05:36 AM.